Pad driver

ABSTRACT

A pad driver for use with a floor maintenance machine that includes a riser portion and a driver disc portion that defines a driving surface which is engageable with a floor maintenance pad. The riser includes a radial flange which extends outwardly from a central hub. The radial flange includes a rim portion supported radially outwardly from the hub by a plurality of spoke-like regions. Regions of reduced material thickness separate the spoke-like regions. The hub is generally cup-shaped and includes a planar upper disc portion and a stepped, transition portion that joins the upper disc portion with the radial extending flange. A plurality of radially extending, rigidizing axial ribs extend between the underside of the upper disc portion and the inside of the stepped transition portion. The driver disc portion may comprise a separate driver disc attached to the riser or alternately, comprise a plurality of driving elements molded into the radial flange. The radial flange is preferably angled at approximately 5° with respect to a horizontal plane that is orthogonal to a rotational axis of the riser when the rotational axis is oriented vertically. A clutch member portion for rotatably coupling a drive motor forming part of the floor maintenance machine to the riser may be integrally formed in the riser or alternately, be defined by a separate clutch member suitably attached to the riser. The pad driver may comprise an assembly made up of individual elements or alternately, be molded as a single unit from a polymeric material, such as glass filled nylon.

TECHNICAL FIELD

[0001] The present invention relates generally to floor cleaning and maintenance machines and in particular to a pad driver for transferring rotative forces from a drive source forming part of the floor maintenance machine to a floor maintenance particularly a cleaning, buffing, scouring or waxing pad.

[0002] Background Art

[0003] Floor maintenance machines used for cleaning, polishing and waxing floor typically include a pad driver that is rotatably connected to a drive motor. The pad driver includes a driver disc that is engageable with a floor maintenance pad. The driver disc includes structure by which is frictionally coupled to the pad, such that rotation of the driver disc produces attendant rotation in the maintenance pad. An example of a driver disc to which this invention pertains is illustrated in U.S. Pat. No. 6,108,856, which is owned by the assignee of the present application and is hereby incorporated by reference.

[0004] Although the driver disc disclosed in the above-identified '856 patent works satisfactorily for most applications, it has been found that under some operating conditions, perimeter regions of the floor maintenance pad which is engaged by the driver disc do not contact the floor being cleaned with the same contact pressure as other parts of the floor maintenance pad.

DISCLOSURE OF INVENTION

[0005] The present invention provides a new and improved pad driver which produces more uniform contact pressure between a floor maintenance pad, engaged by the pad driver, and the floor being cleaned.

[0006] According to one embodiment of the invention, the pad driver includes a riser that has a radial flange which extends outwardly from a central hub. The radial flange includes a rim portion supported radially outwardly from the hub by a plurality of spoke-like regions. The radial flange is angled downwardly with respect to a horizontal plane that is orthogonal to a rotational axis of the riser, when the rotational axis is oriented vertically. In the illustrated embodiment, the radial flange is angled approximately 5°.

[0007] According to a feature of this embodiment, the hub is cup-shaped and includes an upper disc portion and a transition segment which joins the disc portion to the radial flange. A plurality of rigidizing ribs are molded into the hub and extend between an underside of the disc portion and an inside of the stepped, transition portion. In the preferred and illustrated embodiment, reduced material regions are located between the spoke-like regions and are triangularly shaped. In an alternate embodiment, these regions are defined by holes in the radial flange.

[0008] In one embodiment, a driver disc is suitably secured to the riser and defines a driving surface which is engageable with a floor maintenance pad. In an alternate embodiment, the driving surface for drivingly engaging the floor maintenance pad is molded on the underside of the riser. In the illustrated embodiment, the driving surface comprises a plurality of arrowhead members that provide a hook and loop type engagement with a cleaning pad, as well as a plurality of spike-like members which also drivingly engage the cleaning pad held to the riser by the arrowhead members.

[0009] According to the invention, a clutch member for operatively coupling the floor maintenance machine to the riser may be suitably secured to the hub portion of the riser.

[0010] Alternately, a clutch member structure may be integrally molded as part of the riser. The present invention thus provides a cost effective pad driving device which may take advantage of molding techniques to produce an inexpensive pad driver with improved performance. The disclosed construction results in a pad driver that exerts more uniform and consistent pressure to a cleaning pad during operation of the floor maintenance machine. The pad driver may comprise individually molded riser and driver disc members. Alternately the pad driver may be entirely molded from a suitable polymeric material such as glass filled nylon.

[0011] Additional features of the invention will become apparent and a fully understanding obtained by reading the following detailed description made in connection with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0012]FIG. 1 is a side view of a floor maintenance machine and a pad assembly, portions of which are shown in section;

[0013]FIG. 2 is a bottom elevational view of a riser and driver disc, constructed in accordance with a preferred embodiment of the invention, with portions broken away to show additional details;

[0014]FIG. 3 is a sectional view of the riser and driver disc as seen from the plane indicated by the line 3-3 in FIG. 2;

[0015]FIG. 4 is a bottom elevational view of a riser constructed in accordance with a second embodiment of the invention;

[0016]FIG. 5 is a sectional view as seen from the plane indicated by the line 5-5 in FIG. 4, shown with a pad attached to the riser;

[0017]FIG. 6 is a bottom elevational view of a riser constructed in accordance with a third embodiment of the invention;

[0018]FIG. 7 is a sectional view as seen from the plane indicated by the line 7-7 in FIG. 6, shown with a pad attached to the riser; and,

[0019]FIG. 8 is a fragmentary perspective view of a protrusion for engaging a pad that may form part of the driver disc shown in FIG. 1, or the riser shown in FIGS. 4 and 6.

BEST MODE FOR CARRYING OUT THE INVENTION

[0020]FIG. 1 illustrates, somewhat schematically, a floor maintenance machine 20 which, as is conventional, is used to perform a variety of floor related maintenance tasks. For example, the machine 20 may be used to buff, clean, polish, scrub or scour a floor surface. Generally, the machine 20 is used in industrial and commercial floor maintenance applications.

[0021] In general, the machine 20 includes a housing 21 which typically encloses an electric drive motor (not shown). At least one pair of wheels 22 is normally attached to the housing 21 to facilitate movement of the machine 20 from location to location. An operator handle 23 extends upwardly from the housing 21 and is used to control movement of the machine i.e. to pull, push and guide the machine.

[0022] As is also conventional, a pad drive member 27 depends downwardly from a rotatable hub 24; the hub 24 is connected directly or indirectly to the drive motor (not shown), such that rotation of the electric drive motor produces attendant rotation in the drive member 27. In the illustrated embodiment, the drive member 27 includes a plurality of radially extending drive lugs 28 that are symmetrically spaced around the periphery of the drive member 27 and are spaced a predetermined distance below an abutment surface 26 defined by the hub 24. The lugs 28 have a top surface 30 adapted to engage structure (to be described) forming part of a pad driver.

[0023] The drive member 27 is adapted to releasably engage a pad driver 40 to which a pad 42 is attached. The pad driver 40 includes structure drivingly engageable by the lugs 28 such that rotation of the drive member 27 produces attendant rotation in the pad 42 via the pad driver 40. An example of the type of structure that is engageable by the drive lugs 28 is illustrated and disclosed in U.S. Pat. No. 5,645,365, which is hereby incorporated by reference.

[0024] The pad driver 40 shown in FIG. 1 is constructed in accordance with one preferred embodiment of the invention. Referring also to FIGS. 2 and 3, in this embodiment, the pad driver 40 includes a riser 50 and a driver disc 52. The driver disc 52 may be constructed in accordance with U.S. Pat. No. 6,108,856 which is hereby incorporated by reference. As more fully described in the '856 patent, the driver disc includes a driving surface which is engageable with a cleaning, buffing, waxing or scouring pad. The driving surface of the driver disc 52 includes a plurality of sets of outwardly projecting protrusions, indicated generally by the reference character 60 in FIG. 2. As shown in FIG. 8, these protrusions 60 may comprise circular array “arrowhead” members 60 a of the type illustrated and described in the '856 patent. The projections 60 (again, as more fully described in the '856 patent) provide a “hook and loop” type engagement with a pad 42 such that rotation of the pad driver 40 produces rotation in the pad 42.

[0025] In the embodiment illustrated in FIGS. 2-3, the driver disc 52 is secured to the riser 50 by suitable fasteners 62. As seen best in FIG. 2, the riser 50 includes a radial flange 50 a which extends outwardly from a central hub 50 b. In the preferred and illustrated embodiment, the radial flange 50 a and central hub 50 b are integrally molded. The hub 50 b is generally cup-shaped and includes a planar, upper disc portion 66 having a top surface 66 a. A stepped transition segment 68 joins the upper disc portion 66 with the radially extending flange 50 a. Referring in particular FIG. 2, a plurality of radially extending axial ribs or gussets 69 extend between the underside of the disc portion 66 and the inside of the stepped, transition portion 68 and serve to rigidize the hub 50 b without adding unnecessary weight. As also seen best in FIG. 2, a plurality of bosses 70 are also molded on the underside of the hub 50 b and are adapted to receive the fasteners 62 which secure the driver disc 52 to the riser 50.

[0026] In the embodiment illustrated in FIGS. 2 and 3, the structure for engaging the drive 28 of the drive member 27 is provided by a clutch member 74 which is secured to the hub by a plurality of fasteners 76. The clutch member 74 may be the same or similar to the clutch member illustrated in the '365 patent. In this embodiment, the hub 50 b includes a plurality of bosses 78 which are adapted to received the fasteners 76 for securing the clutch member 74 to the hub 50 b.

[0027] For applications which do not require a releasable connection between the machine 20 and the pad driver 40 shown in FIG. 1, the hub SOb may be attached directly to the machine drive hub 24 by suitable fasteners.

[0028] As seen best in FIG. 3, the radial flange 50 a extends outwardly from the base or lower portion 68 a of the stepped, transition segment 68. In the preferred embodiment, the radial flange 50 a is angled downwardly with respect to a horizontal plane that is orthogonal to a rotational axis 80 of the riser 50. In the preferred embodiment, the angle is approximately 5 degrees. The flange 50 a includes a plurality of triangular shaped recesses 84 which serve to reduce the amount of material needed to mold the riser 50 without unduly sacrificing component strength. For some applications, the recesses may be replaced with similarly shaped apertures or through holes. As seen in FIG. 2, the recesses define a plurality of spoke like regions 88 which extend radially from the hub 50 b to an outer, circular rim portion 90. The regions 88 have a greater thickness and hence greater strength than the recesses 88. In applications here the recesses are replaced with holes, the regions 88 in fact become spokes. In the preferred and illustrated embodiment, the spoke like regions are tapered such that an radially inner portion is wider that a radially outer portion.

[0029] The angularity of the flange 50 a, as seen in FIG. 1, tends to urge the outer portions of the cleaning pad 42 in contact with the floor and tends to inhibit the outermost periphery of the cleaning pad 42 for moving upwardly, out of contact with the floor when the pad driver is rotating 40. In other words, the construction of the pad driver 40 and the molded in angle of the flange portion 50 a ends to maximize contact between the underside of the cleaning pad 42 and the floor.

[0030] In the embodiment illustrated in FIG. 3 and as discussed above, the drive lug engagement structure forms part of a separate clutch member 74 that is suitably secured by fasteners, to the hub 50 b. The “spoked” structure of the flange 50 a enables the riser and attached driver disc to exert pressure on the pad 42 to maintain contact of the outer periphery of the cleaning pad with the floor while not increasing the weight of the pad driver beyond desired limits.

[0031] In the preferred embodiment the riser 40 is preferably molded from a suitable polymeric material, such as glass filled nylon. The riser 50 and the driver disc 52 can both be easily be manufactured using plastic injection molding techniques which can be used to produce consistent high quality parts that are cost effective.

[0032]FIGS. 4 and 5 illustrate another embodiment of the invention. In this embodiment, a riser 50′ is used that eliminates the need for a separate driver disc such as the driver disc 52 shown in FIGS. 1-3. The construction of the riser 50′ is similar to the construction of the riser 50 shown in FIGS. 2 and 3. To facilitate the explanation like parts will be given the same reference character followed by an apostrophe.

[0033] The riser 50′ includes hub and flange portions 50 a′, 50 b′ which are similar in construction to the hub and flange portions 50 a, 50 b shown in FIGS. 2 and 3. This embodiment may be used with a separate clutch member 74′ that is secure to the hub 50 b′ by fasteners 76′. Alternately, the riser 50′ can be bolted directly to the hub of a cleaning machine. In this embodiment, the hub 50 b′ also includes rigidizing gussets or ribs 69 that extend between a transition segment 68′ and the underside of the upper disc portion 66′. Like the embodiment of FIGS. 2 and 3, in this embodiment the flange 50 a′ includes triangular recesses 84′ and radially extending spoke like regions 88′ which extend from the hub 50 b′ to a rim portion 90′.

[0034] Unlike the embodiment of FIGS. 2 and 3, in this embodiment, protrusions, indicated generally by the reference character, 60′ are molded directly into the flange portion 50 a′ of the riser 50′ thus eliminating the need for a separate driver disc 52 (shown in FIGS. 1-3). The protrusions 60′ may be the same or similar to those shown in FIG. 8. In addition, a plurality of spike like elements 94 are also molded into the underside of the riser 50′. As explained above, the protrusions 60′ provide a “hook and loop” type engagement between the riser 50′ and a cleaning pad 42. This type of engagement maintains the position of the pad with respect to the riser even when the machine is pivoted about its wheels and the pad is raised off the floor.

[0035] The spike members 94 provide an additional driving engagement between the riser 50′ and pad 42 when the machine 20 is in the operative position and the pad is in engagement with the floor surface.

[0036]FIGS. 6 and 7 illustrate another embodiment of the invention which is similar to the embodiment shown in FIGS. 4 and 5. Like the embodiment shown in FIGS. 4 and 5, the embodiment of FIGS. 6 and 7 provides a riser 50″ with integrally molded protrusions 60″ and spike members 94′ which eliminate the need for a separate driver disc. In this preferred embodiment however, the machine engagement structure (that is engageable by the drive lugs 28 of the machine drive member 27, see FIG. 1) is integrally molded into the hub portion 50 b″. In the embodiment of FIGS. 4 and 5, the machine engagement structure forms part of a separate clutch member 74′ that is secured to the riser hub 50 b′. In this third embodiment, the structure 74″ is integrally molded as part of the riser 50″.

[0037] As more fully disclosed in the '365 patent, the machine engagement structure 74″ includes openings 100 through which the drive lugs 28 of the drive member 27 can pass. One the lugs 27 have passed through the openings 100, relative rotation of the riser 50″ with respect to the drive member 27 causes the lugs 28 to engage the underside of clutch fingers 102 that form part of the engagement structure 74″ molded as part of the riser 50″. The clutch fingers 102 have ramp like surfaces that lock the fingers 102 and hence the hub 50 b″ between the lugs 27 and the bottom surface 26 of the machine hub 24 (see FIG. 1). Reverse relative rotation between the riser 50″ and the machine drive member 27 releases the engagement between the drive member 27 and the hub 50 b″ and allows the riser 50″ to be released from the machine 20.

[0038] Although the invention has been described with a certain degree of particularity it should be understood that those skilled in the art can make various changes to it without departing from the spirit or scope of the invention as hereinafter claimed. 

We claim:
 1. A pad driver for use with a floor maintenance machine having a pad driver motor, comprising: a) a driver disc having a driving surface which is engageable with a floor maintenance pad; b) a riser to which the driver disc is attached; c) said riser including a radial flange which extends outwardly from a central hub; d) said hub being generally cup-shaped and including a planar, upward disc portion having a top surface; e) structure defining a stepped transition segment that joins said upper disc portion with said radially extending flange; f) a plurality of radially extending axial ribs that extend between an underside of the upper disc portion and an inside of said stepped, transition portion; and, g) a plurality of bosses integrally molded on an underside of the hub, said boss is adapted to receive fasteners by which said driver disc is secured to said riser.
 2. The pad driver of claim 1, further comprising a clutch member attached to said hub by which said driver is releasably engaged by said pad drive motor.
 3. The pad driver of claim 1, wherein said radial flange and central hub are integrally molded as a unitary unit.
 4. A pad driver for use with a floor maintenance machine having a pad driver motor, comprising: a) a riser portion defining a radial flange which extends outwardly from a central hub; b) said radial flange including spoke-like regions separated by recessed regions; c) a driver disc portion for drivingly engaging a pad whereby rotation of said hub portion produces rotation in said pad; and, d) said radial flange being angled downwardly with respect to a horizontal plane that is orthogonal to a rotational axis of the riser when the axis is oriented vertically.
 5. The pad driver of claim 4, wherein said radial flange is angled at approximately 5° with respect to the horizontal plane.
 6. The pad driver of claim 4, wherein said driver disc portion comprises a separate driver disc having pad driving elements thereon, said driver disc being suitably secured to said riser.
 7. The pad driver of claim 4, wherein said recesses are substantially triangularly shaped.
 8. The pad driver of claim 3, wherein said hub is generally cup-shaped and defines a transition segment that joins an upper disc portion of said hub with the radially extending flange.
 9. The pad driver of claim 8, further comprising a plurality of radially extending axial ribs that extend between an underside of said disc portion and an inside of said step transition portion.
 10. The pad driver of claim 4, wherein said driver disc portion includes a plurality of protrusions and spike-like elements for drivingly engaging a pad.
 11. The pad driver of claim 4, further comprising a clutch member portion engageable with driving structure forming part of said floor maintenance machine.
 12. The pad driver of claim 11, wherein said clutch member portion is integrally molded with said riser.
 13. A pad driver for use with a floor maintenance machine having a pad driver motor, comprising: a) a riser including a central hub and a substantially radial flange extending outwardly from said hub; b) structure for drivingly engaging a pad such that rotation of said riser produces attendant rotation in said pad; c) said radial flange including an outer rim portion and spoke-like regions extending from said hub to said rim portion; d) said radial flange further defining regions of reduced material thickness intermediate said spoke-like regions; and, e) said radial flange being angled downwardly with respect to a horizontal plane that is orthogonal to a rotational axis of said riser when said rotational axis is vertically oriented.
 14. The pad driver of claim 13, wherein said regions of reduced material thickness comprise holes in said radial flange.
 15. The pad driver of claim 13, wherein said hub includes a transition segment that joins a disc portion forming part of said hub with said radial flange and further includes a plurality of rigidizing gussets that extend between said transition segment and the underside of said disc portion.
 16. The pad driver of claim 13, wherein said pad driving portion comprises a driver disc including a plurality of pad driving elements, said driver disc being suitably secured to said riser.
 17. The pad driver of claim 13, further including a clutch member integrally molded with said riser and including structure operatively engageable with said drive motor of said floor maintenance machine.
 18. The pad driver of claim 13, wherein said riser is molded from a polymeric material.
 19. The pad driver of claim 18, wherein said riser is molded from a glass filled nylon.
 20. The pad driver of claim 17, wherein said clutch member includes clutch fingers separated by openings which cooperate to engage lugs forming part of said floor maintenance machine upon predetermined relative rotation between said clutch member and said driver lugs.
 21. A molded pad driver for use with a floor maintenance machine having a pad driver motor, comprising: a) a riser portion including a radial flange which extends outwardly from a central hub; b) said radial flange comprising a rim portion supported radially outwardly from said hub portion by a plurality of spoke-like regions; c) said spoke-like regions separated by regions of reduced material thickness; d) said radial flange defining a pad driving surface that includes a plurality of driving elements molded into said flange; and, e) said radial flange being angled downwardly at approximately 5° with respect to a horizontal plane that is orthogonal to a rotational axis defined by said hub when said rotational axis is oriented vertically.
 22. The pad driver of claim 21, wherein said driving elements comprise a plurality of arrow-shaped members.
 23. The pad driver of claim 21, wherein said driving elements comprise a plurality of spike-like members.
 24. The pad driver of claim 21, wherein said riser includes a plurality of rigidizing gussets for strengthening a transition segment forming part of said hub and from which said radial flange extends.
 25. The pad driver of claim 21, further including an integrally molded clutch portion by which said riser is operatively engaged by said floor maintenance machine so that rotation of said driver motor produces rotation in said riser. 